Optimization of labeling dipicolylamine derivative, N,N'-(5-(4-aminobutoxy)-1,3-phenylene)bis(methylene)bis(1-(pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine), with three 18F-prosthetic groups as potential imaging agents for metastatic infectious disease

The aim of this study was to develop 18?F-labeled dipicolylamine derivative (compound 1) with three 18?F-prosthetic groups, 18?F-NFP, 18?F-SFB, and 18?F-FET, which were synthesized with labeling yields of 72 +/- 10%, 75 +/- 8%, and 90 +/- 8%, respectively. Compound 1 was then conjugated with 18?F-NFP, 18?F-SFB, and 18?F-FET, respectively. Factors such as the amount of 1, reaction temperature, and time were examined to optimize the yields. The optimal labeling conditions were found to be 1 (0.1?mg, 0.17?mu mol), room temperature, and 10?min for both 18?F-NFP and 18?F-SFB; 1 (4?mg, 6.8?mu mol), 100?degrees C, and 10?min for 18?F-FET. The total synthesis time, the overall yields, and the average specific activity were 105, 75, and 65?min; 68 +/- 9%, 71 +/- 11%, and 76 +/- 13%; 625?Ci/mmol, 853?Ci/mmol, and 3.5?Ci/mmol for 18?F-FP-1,18F-FB-1, and 18?F-FE-1, respectively (n?=?5, decay-corrected based on 18F). Copyright (c) 2012 John Wiley & Sons, Ltd.